The Criterion M1A/M14 G.I. contoured barrels are properly timed and have all threading and milling operations performed. These hand lapped parkerized 4150 CMV barrels come standard with a 7.62 NATO .010 short chamber. Our M1A/M14 barrels can also be purchased chrome-lined with a finished chamber. Each barrel will require headspacing and installation by a qualified gunsmith.